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There are a lot of “12 CS books every programmer must read” lists floating around out there. That's nonsense. The field is too broad for almost any topic to be required reading for all programmers, and even if a topic is that important, people's learning preferences differ too much for any book on that topic to be the…
Since early this year, Michael Malis (of pgrust ) has been showing me interesting things he's done and saying
The other day, I saw a viral tweet saying that people talking about how LLMs are causing slow, bloated, code are going to eat crow once they re-write everything in super-optimized assembly. We're not quite at the point where we want to write everything in assembly , but some variant of what Nolan Lawson said about…
I've been comparing notes with people who run corporate engineering blogs and one thing that I think is curious is that it's pretty common for my personal blog to get more traffic than the entire corp eng blog for a company with a nine to ten figure valuation and it's not uncommon for my blog to get an order of…
Wave is a $1.7B company with 70 engineers 1 whose product is a CRUD app that adds and subtracts numbers. In keeping with this, our architecture is a standard CRUD app architecture, a Python monolith on top of Postgres. Starting with a simple architecture and solving problems in simple ways where possible has allowed…
I haven't used a desktop email client in years. None of them could handle the volume of email I get without at least occasionally corrupting my mailbox. Pine, Eudora, and outlook have all corrupted my inbox, forcing me to restore from backup. How is it that desktop mail clients are less reliable than gmail, even…
Reaching 95%-ile isn't very impressive because it's not that hard to do. I think this is one of my most ridiculable ideas. It doesn't help that, when stated nakedly, that sounds elitist. But I think it's just the opposite: most people can become (relatively) good at most things.
I used to wonder why I see so many more bugs than most people. I easily observe hundreds to thousands of bugs per week and nothing seems to work , but most people I talk to don't see anything like this . For a long time, I thought this had something to do with how I use computers but, over time, I've realized that…
Tavish Armstrong has a great document where he describes how and when he learned the programming skills he has . I like this idea because I've found that the paths that people take to get into programming are much more varied than stereotypes give credit for, and I think it's useful to see that there are many possible…
This is one of those “N technical things every programmer must read” lists, except that “programmer” is way too broad a term and the styles of writing people find helpful for them are too different for any such list to contain a non-zero number of items (if you want the entire list to be helpful to everyone). So…
In the fall of 2000, I took my first engineering class: ECE 352 , an entry-level digital design class for first-year computer engineers. It was standing room only, filled with waitlisted students who would find seats later in the semester as people dropped out. We had been warned in orientation that half of us…
When I ask people at trendy big tech companies why algorithms quizzes are mandatory, the most common answer I get is something like "we have so much scale, we can't afford to have someone accidentally write an O(n^2) algorithm and bring the site down" 1 . One thing I find funny about this is, even though a decent…
This somewhat widely cited post (I keep seeing it cited, anyway) suggests that dynamic languages and/or languages that represent things more concisely are more token efficient. It seems to be cited enough that LLM search results agree. For example, when I searched for "dynamic vs static language token cost" (no…
My hobby : opening up McIlroy’s UNIX philosophy on one monitor while reading manpages on the other.
In the classic 1986 essay, No Silver Bullet , Fred Brooks argued that there is, in some sense, not that much that can be done to improve programmer productivity. His line of reasoning is that programming tasks contain a core of essential/conceptual 1 complexity that's fundamentally not amenable to attack by any…
This is a psuedo-transcript for a talk given at Deconstruct 2019. To make this accessible for people on slow connections as well as people using screen readers, the slides have been replaced by in-line text (the talk has ~120 slides; at an average of 20 kB per slide, that's 2.4 MB. If you think that's trivial…
This is an archive of the original "fsyncgate" email thread. This is posted here because I wanted to have a link that would fit on a slide for a talk on file safety with a mobile-friendly non-bloated format .
This is basically an expanded explanation of what I did after reading this tutorial by Marwan Burelle and then sitting down and trying to write my own implementation, so the steps are going to be fairly similar. The main implementation differences are that my version is simpler and more vulnerable to memory…
A question I get asked with some frequency is: why bother measuring X, why not build something instead? More bluntly, in a recent conversation with a newsletter author, his comment on some future measurement projects I wanted to do (in the same vein as other projects like keyboard vs. mouse , keyboard , terminal and…
Someone : Did you hear that Facebook/Google uses a giant monorepo? WTF! Me : Yeah! It's really convenient, don't you think? Someone : That's THE MOST RIDICULOUS THING I've ever heard. Don't FB and Google know what a terrible idea it is to put all your code in a single repo? Me : I think engineers at FB and Google are…
We previously noted that, while it's easier than ever to hit a particular quality bar by having coding agents use effective test techniques, software quality seems to be getting worse , indicating that whatever defaults developers are using may not work very well. Here, we test if simple instructions to agents to use…
There's been a lot of talk about the vulnpocalypse, to which I don't have much to add because I'm not a security person, but I haven't seen much discussion on the closely related (and to be fair, less serious, issue), the benchmarkpocalypse.
I've been using AI fairly heavily since last November and the whole thing is a funny experience . An agent will do something that, if a human did it, you'd immediately fire them. My reaction, of course, is to act as if this is great and spin up a thousand agents so they can do even more of that.
Here's a language that gives near-C performance that feels like Python or Ruby with optional type annotations (that you can feed to one of two static analysis tools ) that has good support for macros plus decent-ish support for FP, plus a lot more. What's not to like? I'm mostly not going to talk about how great Julia…
How much overhead should we expect from enabling integer overflow checks? Using a compiler flag or built-in intrinsics, we should be able to do the check with a conditional branch that branches based on the overflow flag that add and sub set. Code that looks like
Here's the graph of a toy benchmark 1 of page-aligned vs. mis-aligned accesses; it shows a ratio of performance between the two at different working set sizes. If this benchmark seems contrived, it actually comes from a real world example of the disastrous performance implications of using nice power of 2 alignment…
Verilog is the most commonly used language for hardware design in America (VHDL is more common in Europe). Too bad it's so baroque. If you ever browse the Verilog questions on Stack Overflow , you'll find a large number of questions, usually downvoted, asking “why doesn't my code work?”, with code that's not just a…
We’re going to reproduce some results from papers on filesystem robustness that were written up roughly a decade ago : Prabhakaran et al. SOSP 05 paper , which injected errors below the filesystem and Gunawi et al. FAST 08 , which looked at how often filesystems failed to check return codes of functions that can…
I recently had a problem where part of the solution was to do a series of pointer accesses that would walk around a chunk of memory in pseudo-random order. Sattolo's algorithm provides a solution to this because it produces a permutation of a list with exactly one cycle, which guarantees that we will reach every…
I love reading postmortems. They're educational, but unlike most educational docs, they tell an entertaining story. I've spent a decent chunk of time reading postmortems at both Google and Microsoft. I haven't done any kind of formal analysis on the most common causes of bad failures (yet), but there are a handful of…